Directional Sensitivity In Light-Mass Dark Matter Searches With Single-Electron Resolution Ionization Detectors [CL]

http://arxiv.org/abs/1703.05371


We present a method for using solid state detectors with directional sensitivity to dark matter interactions to detect low-mass Weakly Interacting Massive Particles (WIMPs) originating from galactic sources. In spite of a large body of literature for high-mass WIMP detectors with directional sensitivity, there is no available technique to cover WIMPs in the mass range <1 GeV. We argue that single-electron resolution semiconductor detectors allow for directional sensitivity once properly calibrated. We examine commonly used semiconductor material response to these low-mass WIMP interactions.

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F. Kadribasic, N. Mirabolfathi, K. Nordlund, et. al.
Fri, 17 Mar 17
32/50

Comments: N/A

Aqua MODIS Band 24 Crosstalk Striping [IMA]

http://arxiv.org/abs/1703.04719


Aqua MODIS, unlike its predecessor on board the Terra spacecraft, had always been thought to have been spared from significant deleterious impacts of electronic crosstalk on its imagery. However, recent efforts brought to our attention the presence of striping artifacts in Aqua MODIS images from band 24 (4.47$\mu$m), which upon further inspection proved to have a noticeable impact on the quality of the L1B product and to have been present since the beginning of the mission, in 2002. Using images of the Moon from scheduled lunar observations, we linked the artifacts with electronic crosstalk contamination of the response of detector 1 of band 24 by signal sent from the detector 10 of band 26 (1.375$\mu$m), a neighboring band in the same focal plane assembly. In this paper, we report on these findings, the artifact mitigation strategy adopted by us, and on our success in restoring band 24 detector 1 behavior and image quality.

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G. Keller, Z. Wang, A. Wu, et. al.
Thu, 16 Mar 17
24/92

Comments: N/A

The Novel ABALONE Photosensor Technology [CL]

http://arxiv.org/abs/1703.04546


The patented and proven ABALONE Photosensor Technology (Daniel Ferenc, U.S. Patent 9,064,678, 2010) has the capability of opening new horizons in the fields of fundamental physics, functional medical imaging, and nuclear security. This article discusses our new technology and overviews the unprecedented performance of ABALONE Photosensors, produced in the custom designed production line at UC Davis and continuously tested since 2013. In conclusion, the modern ABALONE Technology is far superior to prior art in performance, robustness and the capacity for integration into large area detector shells. It is about two orders of magnitude more cost effective while being mass-producible with a relatively low investment.

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D. Ferenc, A. Chang and M. Ferenc
Thu, 16 Mar 17
44/92

Comments: 16 pages, 7 figures, Submitted for publication to Nuclear Instruments And Methods In Physics Research A on March 12, 2017 (Ms. Ref. No.: NIMA-D-17-00243)

Gain factor and parameter settings optimization of the new gamma-ray burst polarimeter POLAR [IMA]

http://arxiv.org/abs/1703.04210


As a space-borne detector POLAR is designed to conduct hard X-ray polarization measurements of gamma-ray bursts on the statistically significant sample of events and with an unprecedented accuracy. During its development phase a number of tests, calibrations runs and verification measurements were carried out in order to validate instrument functionality and optimize operational parameters. In this article we present results on gain optimization togeter with verification data obtained in the course of broad laboratory and environmental tests. In particular we focus on exposures to the $^{137}$Cs radioactive source and determination of the gain dependence on the high voltage for all 1600 detection channels of the polarimeter. Performance of the instrument is described in detail with respect to the dynamic range, energy resolution and temperature dependence. Gain optimization algorithms and response non-uniformity studies are also broadly discussed. Results presented below constitute important parts for development of the POLAR calibration and operation database.

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X. Zhang, W. Hajdas, H. Xiao, et. al.
Tue, 14 Mar 17
17/74

Comments: 22 pages, 14 figures

Sensitivity Characterization of a Parametric Transducer for Gravitational Wave Detection Through Optomechanical Spring Effect [IMA]

http://arxiv.org/abs/1703.02179


We present the characterization of the most recent parametric transducers designed to enhance the Mario Schenberg Gravitational Wave Detector sensitivity. The transducer is composed of a microwave re-entrant cavity that attaches to the gravitational wave antenna via a rigid spring. It functions as a three-mode mass-spring system; motion of the spherical antenna couples to a 50 $\mu$m thick membrane, which converts its mechanical motion into a frequency shift of the cavity resonance. Through the optomechanical spring effect, the microwave transducer frequency-displacement sensitivity was measured to be 726 MHz/$\mu$m at 4 K. The spherical antenna detection sensitivity is determined analytically using the transducer amplification gain and equivalent displacement noise in the test setup to be $5.5 \times 10^{-19}\sqrt{Hz}^{-1}$.

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N. Carvalho, J. Bourhill, O. Aguiar, et. al.
Wed, 8 Mar 17
26/60

Comments: N/A

Search for axions in streaming dark matter [CL]

http://arxiv.org/abs/1703.01436


A new search strategy for the detection of the elusive dark matter (DM) axion is proposed. The idea is based on streaming DM axions, whose flux might get temporally enormously enhanced due to gravitational lensing. This can happen if the Sun or some planet (including the Moon) is found along the direction of a DM stream propagating towards the Earth location. The experimental requirements to the axion haloscope are a wide-band performance combined with a fast axion rest mass scanning mode, which are feasible. Once both conditions have been implemented in a haloscope, the axion search can continue parasitically almost as before. Interestingly, some new DM axion detectors are operating wide-band by default. In order not to miss the actually unpredictable timing of a potential short duration signal, a network of co-ordinated axion antennae is required, preferentially distributed world-wide. The reasoning presented here for the axions applies to some degree also to any other DM candidates like the WIMPs.

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K. Zioutas, V. Anastassopoulos, S. Bertolucci, et. al.
Tue, 7 Mar 17
65/66

Comments: 5 pages

Understanding NaI(Tl) crystal background for dark matter searches [IMA]

http://arxiv.org/abs/1703.01982


We have developed ultra-low-background NaI(Tl) crystals to reproduce the DAMA results with the ultimate goal of achieving purity levels that are comparable to or better than those of the DAMA/LIBRA crystals. Even though the achieved background level does not approach that of DAMA/LIBRA, it is crucial to have a quantitative understanding of the backgrounds. We describe the contributions of background sources quantitatively by performing Geant4 Monte Carlo simulations that are fitted to the measured data to quantify the unknown fractions of the background compositions. The overall simulated background spectrum well describes the measured data with a 9.16-kg NaI(Tl) crystal and shows that the background sources are dominated by surface $^{210}$Pb and internal $^{40}$K in the 2 to 6-keV energy interval, which produce 2.31 counts/day/keV/kg (dru) and 0.48 dru, respectively.

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G. Adhikari, P. Adhikari, C. Ha, et. al.
Tue, 7 Mar 17
66/66

Comments: N/A